Incandescent lamp.



PATENTED JAN. 24,1905.

H. E. MEYERS. INGANDESCENT LAMP.

APPLVIOATION FILED NOV. 24, 1902.

UiKTITED I STATES Patented January 24, 1905 PATENT OFFICE.

HENRY EDWARD MEYERS, OF DENVER, COLORADO, ASSIGNOR TO THE ELECTRIC FLASH LIGHT COMPANY, OF DENVER, COLORADO.

INCANDESCENT LAMP.

SPECIFICATION forming part of Letters Patent No. 780,613, dated January 24;, 1905. 7

Application filed November 24, 1902. Serial No. 132,572.

To crZZ whom, itratcrzrcortoerh: I

Be it known that I, HENRY EDWARD MEYERS, a citizen of the United States, residing at Denver, in the county of Arapahoe and State of Colorado, have invented certain new and useful Improvements in Incandescent Lamps, of which the following is a specification.

My invention relates to incandescent lamps, and more especially to that type consisting of a pair of shells or bulbs one within the other and each provided with a filament, the two filaments electrically connected at one end and insulated at the other; and my object is to produce a device of this character provided With contacts so arranged as to be adapted for use in connection with a socket on which I have an application for patent pending in the Patent Office concurrently with this.

A further object is to produce a device of this character of exceedingly simple and compact construction.

With the above-mentioned objects in view the invention consists in certain novel and peculiar features of construction and organiza' tion, as hereinafter described and claimed, and in order that it may be fully understood reference is to be had to the accompanying drawings, in which Figure 1 is a top plan view of an incandescent lamp embodying my invention. Fig. 2 is a central longitudinal section of the same.

In detail, 1 designates the hollow metallic screw, carrying at its front or upper end the usual insulatory disk 2, having a central contact-plate 3 and a marginal contact-ring 4:, in

sulated from contact-plate 3 and from the threaded screw. Secured within screw 1 by the usual cement 5 is the stem 6 of the globe, which globe consists of an outer shell 7 and an inner shell 8, the former by preference being of clear or crystal glass and the latter of red, blue, green, or other-colored glass. Depending within the outer shell at diametrically opposite points are the glass stems 9, and depending within the inner shell is a similar stem 10, the latter opening into the socket direct instead of into the stem 6 of the globe, as do the stems 9. While the globe may be so blown that the vacuums of the shells shall be I entirely separate from each other, I prefer that they shall be in communication, so as to constitute a single vacuum, and thus permit the air to be exhausted from both shells by way of the usual tip at the bottom of the outer one, and in order that this result may be accomplished the inner one is preferably provided with a small orifice ll.

12 designates the filament of the outer shell, the same being of the usual or any preferred substance and anchored against contact with the inclosing or inclosed shell by means of the connections 18. One end of the filament is connected electrically in the customary manner to the ring I and the opposite or return end to the corresponding end of the inner shell-filament 14:, said ends having a common connection 15 with the screwl, while the opposite end of filament 14 is connected to the I contact-plate 3.

In practice when the current is caused to pass through contact-plate 3 or ring 4: the inner or outer filament is in circuit and the former will produce a light corresponding in color to that of the shell by which it is inclosed, while the outer shell and its filament will produce a light of the usual color if the shell is of common crystal glass, as it will be in most globes; rent shall be caused by any suitable switch mechanism to passthrough the filaments alternately, so as to produce a light of changing color; but as it may be of advantage at times to produce light from both filaments simultaneously I have not described or shown the switch mechanism hereinbefore referred to.

A globe of this character may be used in a three-wire system for signaling at a distance, the direction of the current being controlled by any suitable switch mechanism. It may also be used to advantage on the theatrical stage for foot-lights or for flashing color in harmony with a particular scene. In fact, it will be found of advantage over the ordinary lamps in point of economy and convenience in an indefinite number of connections.

Having thus described the invention, what I claim as new, and desire to secure by Letters Patent, is

It is intended that the cur- An incandescent lamp, comprising a pair of transparent shells, one within the other and formed With a stem in common, a hollow metallic screw, an insulatory cement lining for the screw to hold the stem therein, an insulatory disk carried by said screw and upon the upper end of said lining; a contact-ring 4, secured to the upper side of the disk, a central contact-plate 3, secured at the upper side of the disk and provided with a tubular portion depending through said disk, a conductor 15 extending from the screw through the cement lining, a filament 12 within the outer shell 

